To be more clear, a group of ferrets is called a business.

Shouldn’t a guinea pig be a… guinea pig?  I really don’t hear about guinea pigs being used as guinea pigs in experiments, either.  It’s all about the mice and rats and such!

Ad libitum means that it’s at his pleasure, so he can consult strategy whenever he feels like it.  The term is really used more in music and such, where it means you don’t really have to follow the normal rules, like timing and such.  See: Jazz.